1. Field of the Invention
The present invention relates to a camera having at least one push button in the rear surface thereof.
2. Description of the Related Art
Recent compact cameras are added various functions, for example, automatic exposure control function, strobe function, zoom function, liquid crystal indicating function and so forth. For that reason, a plurality of switches besides a main switch are provided on the surface of the camera.
As the switches, slide switches and push switches are employed and are made proper use in accordance with purposes. The push switch is more simple than the slide switch in contact mechanism with a control circuit unit so that the push switch has advantages of easy handling. These switches are generally provided on the rear surface of a camera in view of handling performance of a photographer.
FIG. 3 shows composition of a camera in brief. A camera 10 is composed of a main body 11, a front cover 12 and a rear cover 13. The front cover 12 and the rear cover 13 cover the main body 11 from front and rear thereof respectively. The main body 11 is integrally provided with a cassette chamber 14 and a film take-up camber 15. The cassette chamber 14 contains a cassette shell 16. The film take-up chamber 15 is provided with a spool 18 for winding a photo film 17 advanced from the cassette shell 16.
An exposure aperture 19 is formed between the cassette chamber 14 and film take-up chamber 15. The exposure aperture 19 defines an exposed area and determines the position of the photo film 17 in the optical axis direction in association with a film pressure plate 20 which is attached to the rear cover 13 in elastic manner.
A control circuit board 21 mounting a control circuit of the camera 10 is disposed in a gap between the film pressure plate 20 and the rear cover 13. A liquid crystal indicator 22 and a photographic mode changing button 23 are attached to the control circuit board 21 and are appeared from the rear cover 13.
As shown in FIG. 4, when a push switch is employed as the photographic mode changing button 23, upon operating the photographic mode changing button 23, the force pushing it is supplied toward the film surface of the photo film 17. The film pressure plate 20 biased toward the photo film 17 is disposed between the photographic mode changing button 23 and the photo film 17 so that following problems are occurred. The force pushing the photographic mode changing button 23 is transmitted to the photo film 17 via film pressure plate 20. Thus, a flatness of the photo film 17 is damaged by the force.
Generally, in a conventional camera, when a push switch is employed, a protecting plate 24 is provided between the film pressure plate 20 and the control circuit board 21. Accordingly, the pressure by the pushing operation of the switch is adapted to be not transmitted to the film pressure plate 20. The protecting plate 24 is fixedly secured to the rear cover 13 by means of screws.
However, when the protecting plate is provide as stated above, it is necessary to obtain a space for disposing the protecting plate in a camera. It is also necessary to thicken the protecting plate to a certain degree and to give the protecting plate hardness in order to match the force pushing the switch. Thus, such a camera is prevented from being thinned, and the number of members constituting a camera increases so that it is caused to increase the cost of production.